slow vm migration


Jan 12, 2012

Currently i'm testing two pve boxes. Just tried migrate vm from one box to another, everything works, but is veeeeeery slow. Task viewers output shows me ~11MB/s, but migration is running more than 30mins, percents are counting very slow Vm's size is only 1.5G. On the attached picture with graph is that a MBps ir Mbps?
What can be an issue for such slow migration?
One machine is ibm x3650 M2 with xeon 5504 quad core cpu. Running on LSI Megaraid RAID1 with 2x 7200rpm sas drives. 3GB of ram. CPU usage 8-10%
Other machine is dual core Athlon II X2 250 with single 7200rpm sata hdd. 4GB of ram. CPU usage ~15%
Both machines are connected via desktop 10/100 dumb switch.



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Jan 12, 2012
Looks like a problem is solved. ls -alh /var/lib/vz/images/100/vm-100-disk-1.raw and du -hs /var/lib/vz/images/100/vm-100-disk-1.raw shows a different sizes.
ls shows image size, but du shows a real data size in that image.

Frido Roose

If I understand correctly, you have your VM image on the local file system without using shared storage.
Doing a live migration would require the image to be copied to the other node. Thay may explain the slow migration.
Try using NFS or iscsi for faster migrations.


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